A perilous bid by Welsh adventurer Huw Jack Brassington to conquer one of the world’s toughest mountain challenges while caught in the eye of a ferocious storm has been filmed for a new TV series.

Camera crews followed the former GB triathlete in treacherous conditions as he took on the gruelling Paddy Buckley Round, otherwise known as the Welsh Classical Round.

The endurance challenge sees runners covering a distance of some 100km and climbing 8,000 metres which it the equivalent of scaling Everest, taking in no fewer than 47 summits – all in 24 hours.

It is part of a new five-part documentary, 47 Copa: Her Huw Jack Brassington (47 Summits: Huw Jack Brassington’s Challenge), made by Caernarfon-based Cwmni Da to be screened on S4C, with the first programme being shown at 9.30pm on Wednesday, November 6.

During the most dangerous leg of the challenge, Huw battled 60mph winds and torrential rain as a huge storm hit the Glyderau mountain range in Snowdonia, pushing the boundaries of his strength and endurance further than they have ever been before.

Filming became a dangerous and logistical nightmare for the crew, who described it as the Welsh equivalent to “Armageddon”.

“This challenge was pretty much at the edge of what I can do in good nice weather!” said Huw, 34, who hails from Caernarfon and now lives in Cockermouth, Cumbria.

“Then the storm hit and I’ve never been in weather like it in my life. There were 60 mph winds. It was the kind of weather that normally I wouldn’t think of stepping outside the door.

“We were literally running diagonally! I was running at a 45 degree angle to stay on my feet. The wind was coming and going in gusts and it was hard to keep going.

“I was running like a crab, my legs were in a half squat! At one stage, I looked down at my walking poles and realised I’d lost half of one as it’d smashed in half – my hands were so numb I just hadn’t realised.

“I fell three times. There was always a camera crew around every time! I was cursing them at the time but it is was all down to the well-timed preparation to get these camera guys in the right place at the right time.”

The route takes in the well-known high mountain ranges of Snowdon, the Glyderau and the Carneddau as well as the less visited ranges of Moel Siabod, the Moelwynion, Moel Hebog and the Nantlle Ridge.

The documentary follows Huw’s preparation for the challenge, including his meetings with famous athletes and sportspeople such as white water kayaker Geraint Rowlands, downhill mountain biker Emyr (Ems) Davies, para kayaker Llinos Owen and UFC fighter Brett Johns.

The series was produced and directed by Huw Erddyn, 34, who carefully plotted every stage of the endurance athlete’s journey – but all the planning had to be thrown out of the window.

“The plan was to film on the Friday and Saturday, with Saturday and Sunday as back-up but when we came to work on the Monday morning we realised a massive storm was hitting Snowdonia over the weekend and all that planning we’d done had to be scrapped,” said Huw, who lives in Caernarfon and has known the endurance runner from his secondary school and rugby days.

“We had to bring it all forward a day earlier to avoid the worst of the storm.

“As a result, some of the mountain leaders couldn’t make it and some of the camera crew. The drone pilot was flying back from France and couldn’t get back for the start. We were also hiring a lot of kit and had to resource all of that again.

“At one point we thought Huw would have to run without support runners but people came out to support him and we ended up having a ridiculous amount.

“It was sometime between 3am and 4am on the Friday when the storm hit. It was horrendous. I could hear the wind howling around my van and was really worried about everyone. I’ve not been in the mountains in the middle of a storm like that before.

“With 60 mph winds it was literally Armageddon! The mountain leaders had to hold some of the camera operators while they filmed.

“In a weird way everyone really enjoyed the experience! We were filming someone who was doing something so much harder than we were. We couldn’t really complain about what we were going through. It was nothing compared to what Huw was going through.

“The crew were amazing. Everyone was freezing and soaking wet but they were all still smiling.”

A five-strong crew was recruited for filming during the day including four shooting directors and a drone pilot and another two shooting directors for the night shoot. As producer and director, Huw Erddyn was also a shooting director, poised at the support points throughout the challenge to capture the bulk of the story.

A lot of the crew were experienced mountaineers and climbers and were used to running long distances. One is even a triathlete himself.

“We needed fit camera operators who could run over difficult terrain. There were only a few people up to the job as we were moving at such a high pace,” explained Huw.

“It was a big operation, everyone needed to know what they were doing.

“The storm hit on probably the most treacherous parts of the challenge but Huw was happy to do it.

“There was no way you could put a drone up. A lot of the forward planning had gone out of the window. We were constantly evolving our plans.”

Huw Jack Brassington, who lives with his wife Gwenllian and is a lecturer in engineering at the National College for Nuclear in Cumbria, is no stranger to endurance challenges.

A former Team GB Triathlete, he completed the gruelling BBC Ultimate Hell Week and was previously the focus of another Cwmni Da documentary, also shot by his old school friend Huw Erddyn, as he completed the formidable Berghaus Dragon’s Back Race.

“He has a unique approach to training in that he doesn’t really like to train too much!” explained Huw of the adventure star.

“He doesn’t like to run for the sake of running – instead he finds races to do.

“I have a huge amount of respect for him.”

Huw Jack Brassington added: “A lot of people don’t tell their mates or family they’re doing these kinds of things. Well, think about being followed by five cameras and being filmed falling on your face in a pile of sheep poo! I didn’t even have time to put my hands down!

“I was losing my marbles by the end of it. There’s a lot of pressure in the build-up and it’s a bit of a melting pot and pressure cooker. The more work you put into something the more there is at stake. If I’d fallen at the first leg, then they’d be no film. It was a lot of pressure.

“Huw Erddyn was loving it. You should have seen the smile on his face! He’s a horrible man who likes putting me though pain to make good TV!”

However, the experience has not put him off completing a new endurance challenge.

“My plan is to rotate and wear out different parts of my body at different times and so I’m thinking of cage fighting next!” he said.

“Life is short and I’ve realised that early on. I don’t want to be sitting there aged 80 with any questions like ‘maybe I could’ve run five marathons on the bounce’? I want to be content – even if I’m in pieces. I think your body is there for using in every way possible.”